Switching page to floor plan in my 2 floor 10 apartment SU model is not possible. Longest I waited is 5 minutes - looking at the hourglass (in Windows 10). Went back to Layout 2017 where the page turn takes, on same file, 10 seconds. In my book, even 10 seconds is not acceptable. I do layouts for a living, does not see any alternative but to start looking for a software modern enough.